'No Magic Bullet' Against Zika-Carrying Mosquito, CDC Director SaysCenters for Disease Control and Prevention Director Dr. Tom Frieden visited Miami, where several people have been infected with Zika. He says the CDC is trying to control the mosquito responsible.

'No Magic Bullet' Against Zika-Carrying Mosquito, CDC Director Says

Centers for Disease Control and Prevention Director Dr. Tom Frieden visited Miami, where several people have been infected with Zika. He says the CDC is trying to control the mosquito responsible.

RAY SUAREZ, HOST:

Earlier this week, the CDC issued a Zika travel advisory warning pregnant women against visiting a South Florida neighborhood, a first of its kind in the Continental United States. Dr. Tom Frieden, director of the Centers for Disease Control and Prevention, has been recommending that all pregnant women who've been to the Miami neighborhood of Wynwood over the past six weeks be tested for Zika.

Dr. Frieden joined us now from the CDC to tell us more about his agency's work in Florida and Puerto Rico. I started by asking him to lay out the situation in Miami.

TOM FRIEDEN: The area in Miami that we're concerned about centers on a six-block area where there have been now 13 infections with the Zika virus by mosquitoes confirmed. What we've done with the state of Florida is to define a one-mile radius around that six-block center where we are intensively trying to control the mosquito. And we advised pregnant women not to travel and for pregnant women who have been in that area to get tested for Zika.

SUAREZ: Officials have been aerial spraying there earlier this week. I wanted to ask you about that because there's been some criticism that aerial spraying is not all that effective against this species of mosquito that's considered the culprit, Aedes aegypti.

FRIEDEN: There is no magic bullet against this species. It's really tough to control. We refer to it as the cockroach of mosquitoes because it lives indoors and out. It lives behind furniture and in closets. But what we've found is that aerial spraying with newer technology uses tiny amounts of insecticide and makes it into minuscule droplets that waft through the air, get into more places and kill a larger proportion of the mosquitoes.

SUAREZ: Is it tough to craft a public health message when just the occupants of one single automobile sitting at a red light with the windows rolled down, there's very high risk for some people in that car and fairly low risk for the other passengers?

FRIEDEN: Zika is a challenge in so many ways, and it's been surprising. It's the first time we've ever had a mosquito-borne virus that can cause a human birth defect. It's the first time we've had a mosquito-borne virus that can also be sexually transmitted. But the core message, the core thing to remember about Zika is the real threat is to pregnant women, and our priority is to protect pregnant women.

SUAREZ: There have been efforts to pass special appropriations, to combat Zika in the Continental United States. The first one - $1.9 billion - didn't pass. The second one - smaller at 1.1 billion dollars - didn't pass. Is this a political problem as much as a public health one?

FRIEDEN: The only winner from not having funding for Zika is the Zika virus. One thing that is encouraging is that we've heard from both houses of Congress, from both sides of the aisle that they would like to see some sort of an infectious disease rapid response fund so that the next time there's an emergency, we don't have to go to Congress and ask for emergency money, but we can have the funding and authority to move out rapidly and nip it at the bud, if that's possible.

SUAREZ: Is it too late to stop Zika from becoming an established disease in North America?

FRIEDEN: Well, unfortunately, viruses like Zika are really good at getting into human populations and mosquito populations. So Puerto Rico is currently dealing with really an explosive outbreak of Zika which is affecting a large proportion of people. At least 5 percent of people have already been infected with it. And by the end of this season, it's likely that 20 to 25 percent of people will be infected with it.

And what we've seen with other diseases like Zika is that they do become endemic in places that support their continued transmission. That doesn't include parts of the Continental U.S. where we've been able to control it and get it to go away. That hasn't always been easy, though, but it has been done. And we are hopeful that we'll be able to not have it be present on an ongoing basis endemic in the Continental U.S. Puerto Rico has a much more difficult situation.

SUAREZ: That's Dr. Tom Frieden. He's director of the Centers for Disease Control and Prevention. Good to talk to you, doctor.

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